Meaning

noun an underground tunnel with recesses where bodies were buried (as in ancient Rome)

originFrom Middle English catacombe, from Old English catacumbe, catacumbas pl, from Late Latin catacumbae pl, name of the underground cemetery of St. Sebastian in Rome, of unclear origin. Perhaps a dissimilation (influenced by *cumbō (“to lie, recline”)) of Late Latin cata tumbās (literally “among the tombs”) (from Ancient Greek κατά (katá, “under”) and τύμβος (túmbos, “tomb”)). Some sources suggest…

Etymology from Wiktionary, CC BY-SA 3.0